Sen. John McCain plugged Independent presidential candidate Sen. Bernie Sanders on Wednesday while criticizing his competitor former Secretary of State Hillary Clinton for downplaying the seriousness of recent Veterans Affairs Department scandals.

McCain, R-Arizona, said he was reluctant to offer a favorite to be the Democratic nominee next year but offered that "Bernie worked very hard when he chaired the Senate Veterans Affairs Committee … He does have a record of advocacy for our veterans. I don't know of any legislative activity Hillary engaged in as a Senator."

McCain, chairman of the Senate Armed Services Committee, made his comments during a question and answer session following a joint conference call he made with Rep. Jeff Miller, R-Florida, chairman of the House Veterans Affairs Committee.

The two hosted the call-in with reporters in response to Clinton's recent comment to MSNBC host Rachel Maddow that the VA scandal involving the deaths of some veterans awaiting care at the VA Medical Center in Phoenix was overblown and used by Republicans to score political points.

Clinton told Maddow that the scandal has "not been as widespread as it has been made out to be."

The VA Inspector General's own investigation into Phoenix last year concluded that the problems there were systemic across the VA.

"Hillary Clinton in her blind ambition has now injected partisanship into the VA issue and that is disgraceful," McCain said. "She owes an apology to the families of all those veterans who have served, are serving and particularly the families of those who died -- in particular the 50 who were identified who died awaiting care in the Phoenix VA hospital."

Miller, who has held countless hearings on various VA problems over the past several years, said he does not recall Clinton ever speaking out about the Phoenix scandal when it broke.

"Clinton is a denier of problems at the VA and that's just not appropriate" for a presidential candidate, he said.

McCain's plug for Sanders comes at a time when the Vermont senator has been criticized by the Iraq and Afghanistan Veterans of America for largely ignoring the VA's scandals during his time as chairman of the Senate Veterans Affairs Committee.

Though an Independent, Sanders has caucused with the Democrats in Congress and was given the chairmanship of the veterans' panel when the party held the majority in the chamber.

IAVA Chief Executive Officer Paul Rieckhoff, in interviews with CNN and MSNBC earlier this month, said Sanders played down the crisis in the VA even while the scandals were breaking all around him.

"For far too long he was apologizing for the VA," Rieckhoff told CNN. "He was refusing to acknowledge the severity. He was positioning it as a smaller issue than it was while veterans were dying waiting for care."